Electric motors for use in particular applications typically must be designed to achieve particular performance characteristics, such as speed and torque output for a predetermined load and operating conditions, for example, and to satisfy particular physical constraints, such as motor size and weight, for example. Of course, in designing motors, efforts are also made to minimize the cost as much as possible. When a motor is designed for a given application, testing must be done to ensure that the designed motor meets whatever performance requirements and physical constraints may be specified for that application. However, it is costly to build an actual motor to test the underlying design for compliance with the specified performance requirements and physical constraints and then to refine the design, if necessary, and construct a new motor, sometimes repeatedly, until the final design meets the specified performance.requirements and physical constraints. To avoid some of the cost associated with such construction and testing, modeling techniques have been employed to simulate the performance of new motor designs, using digital computers, for example, to test whether such motor designs comply with specified performance requirements and physical constraints.
While the problem of modeling or simulating the performance of an electric motor is quite complex, prior modeling systems have simplified the problem by making assumptions about the structure and performance of the simulated motor to reduce the amount of computation required to model the motor. Those assumptions oversimplify the problem, however, and the prior modeling systems produce inaccurate simulation results in some cases and are less valuable because they do not accurately represent the performance of the actual motor.